Ophthalmologic apparatus and examination method for eye to be examined

Abstract

To provide an ophthalmologic apparatus that allows a fixation eye for each examination distance in an anisometropic state to be identified.SOLUTION: An ophthalmologic apparatus includes: a visual target projection optical system 4 for presenting a fixation target; a reflex measurement projection system 6 and a reflex measurement light reception system 7 for measuring eye characteristics of right and left eyes to be examined objectively; and a control unit 140 for controlling the reflex measurement projection system 6 and the reflex measurement light reception system 7. The fixation target includes a fusion target capable of fusing an image in a binocular vision state by the right and left eyes to be examined. When the treatment in which one of the eyes to be examined is kept in a complete correction state, and the other of the eyes to be examined is brought into an anisometropic state in which predetermined power correction is made from the complete correction state is performed, the visual target projection optical system 4 presents the fixation target while changing an examination distance from the right and left eyes to be examined to the fixation target in a predetermined distance range. The control unit 140 measures the eye characteristics when viewing the fixation target in binocular vision by the reflex measurement projection system 6 and the reflex measurement light reception system 7, and acquires refractive values of the right and left eyes to be examined.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to an ophthalmic apparatus and a method for examining an eye to be examined. [Background technology]

[0002] Conventionally, there is a treatment called monovision, in which one of the examinee's eyes is corrected to see distant objects and the other is corrected to see close objects, so that the patient can see a range from distant to close objects when viewing with both eyes. When monovision is prescribed, the refractive values ​​(visual acuity) of the left and right examinee's eyes are significantly different, resulting in anisometropia, but there are individual differences in tolerance to anisometropia, and a method is known for predicting the applicability of a monovision prescription (whether or not it is easy to apply monovision) based on the level of ocular dominance (see, for example, Patent Document 1).

[0003] Also, an ophthalmic apparatus is known that allows a subject to experience what a binocular vision looks like with a monovision prescription, thereby verifying whether or not the subject feels uncomfortable (see, for example, Patent Document 2). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2006-122661 A [Patent Document 2] JP 2013-195931 A Summary of the Invention [Problem to be solved by the invention]

[0005] By the way, if the target eye can fixate according to the distance from the test eye to the fixation target in the anisometropic state, it can be considered that the fixation is applicable to the monovision prescription. Therefore, it is possible to accurately evaluate the applicability to the monovision prescription by determining the fixation eye for each test distance in the anisometropic state and determining whether the fixation eye changes with far vision or near vision. However, in the conventional technology, although it is possible to predict the applicability to the monovision prescription based on the level of ocular dominance and to verify the presence or absence of discomfort when viewing with both eyes during monovision prescription, it is not possible to identify the fixation eye for each test distance in the anisometropic state. Here, the "fixation eye" means the test eye that focuses the object on the fovea and captures the image and actively looks at it.

[0006] The present invention has been made in consideration of the above-mentioned problems, and aims to provide an ophthalmic apparatus and a method for examining a subject's eye that can identify the fixating eye for each examination distance in an anisometropic state. [Means for solving the problem]

[0007] In order to achieve the above-mentioned object, the ophthalmic apparatus of the present invention comprises a target presenting unit that presents a fixation target to the left and right test eyes, an objective measurement optical system that objectively measures the ocular characteristics of the left and right test eyes, respectively, and a control unit that controls the objective measurement optical system, wherein the fixation target includes a fusion target that can be fused when viewed binocularly with the left and right test eyes, the target presenting unit presents the fixation target while changing the test distance from the left and right test eyes to the fixation target within a predetermined distance range when a prescription is made such that one of the left and right test eyes is maintained in a completely corrected state and the other of the left and right test eyes is anisometropic corrected by a predetermined degree from the completely corrected state, and the control unit is configured to measure the ocular characteristics when the fixation target is viewed binocularly using the objective measurement optical system and obtain the refractive values ​​of the left and right test eyes as objective measurement information.

[0008] Further, a method for examining an eye to be examined according to the present invention is a method for examining an eye to be examined using an ophthalmic apparatus including a target presenting unit which presents a fixation target to the left and right eyes to be examined, an objective measurement optical system which objectively measures ocular characteristics of the left and right eyes to be examined, and a control unit which controls the objective measurement optical system, in a state in which one of the left and right eyes to be examined is maintained in a perfectly corrected state and the other of the left and right eyes to be examined is corrected from the perfectly corrected state by a predetermined degree to a prescription for anisometropia, the target presenting unit presents the fixation target and changes a test distance from the left and right eyes to the fixation target within a predetermined distance range, and the control unit measures the ocular characteristics when the fixation target is viewed with both eyes to perform objective measurement. The objective measurement method includes a first step of controlling the objective measurement optical system to obtain refractive values ​​of the left and right test eyes as objective measurement information, and a second step of controlling the objective measurement optical system so that after obtaining the objective measurement information in the first step, the other of the left and right test eyes is maintained in the fully corrected state, and one of the left and right test eyes is corrected from the fully corrected state by a predetermined degree to obtain anisometropia, while the target presenting unit presents the fixation target and changes the test distance within the predetermined distance range, and the control unit measures the ocular characteristics when the fixation target is viewed with both eyes, and obtains refractive values ​​of the left and right test eyes as the objective measurement information. Effect of the Invention

[0009] As a result, the ophthalmic apparatus and the method for examining an eye to be examined of the present invention can identify the fixating eye for each examination distance in an anisometropic state. [Brief description of the drawings]

[0010] [Figure 1] 1 is an external perspective view showing an ophthalmic apparatus according to a first embodiment. [Diagram 2] 2 is a schematic diagram showing a configuration example of a left measurement optical system of the ophthalmologic apparatus according to the first embodiment. FIG. [Diagram 3] FIG. 2 is a block diagram showing a control configuration of the ophthalmic apparatus of the first embodiment. [Figure 4]4 is a flowchart showing a flow of a processing procedure of a method for examining an eye to be examined, which is carried out by using the ophthalmologic apparatus of the first embodiment. [Figure 5A] FIG. [Figure 5B] FIG. [Figure 5C] FIG. 2 is an explanatory diagram showing how a left fixation target and a right fixation target are viewed by the left and right test eyes, respectively. [Figure 6A] 1 is a graph showing the test distance and refractive value of the first subject when both eyes were completely corrected. [Figure 6B] 13 is a graph showing the test distance and refraction value at +2D addition for the right eye of the first subject. [Figure 6C] 13 is a graph showing the test distance and refraction value at +2D addition for the left eye of the first subject. [Figure 7A] 13 is a graph showing the test distance and refractive value of the second subject when both eyes were completely corrected. [Figure 7B] 13 is a graph showing the test distance and refraction value at +2D addition for the right eye of the second subject. [Figure 7C] 13 is a graph showing the test distance and refraction value at +2D addition for the left eye of the second subject. [Figure 8A] 13 is a graph showing the test distance and refractive value of the third subject when both eyes were completely corrected. [Figure 8B] 13 is a graph showing the test distance and refraction value at +2D addition for the right eye of the third subject. [Figure 8C] 13 is a graph showing the test distance and refraction value at +2D addition for the left eye of the third subject. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An ophthalmic apparatus and an examination method for an eye to be examined according to the present invention will be described below with reference to a first embodiment shown in the drawings.

[0012] The ophthalmic device 100 of the first embodiment is an eye examination device of a binocular open type capable of measuring the eye characteristics of both eyes simultaneously while the examinee has both eyes open. The ophthalmic device 100 can also measure the eye characteristics of one eye at a time by blocking one eye or turning off the fixation target. The ophthalmic device 100 of the first embodiment is an objective measurement device with a subjective measurement function that has a target presentation function, a phoropter function, and an autoreflex-keratometer measurement function. That is, the examiner can use the ophthalmic device 100 to perform any objective test and subjective test and objectively and subjectively measure the eye characteristics of the examinee's eye E.

[0013] The objective examination that can be performed by the ophthalmic apparatus 100 of the first embodiment includes a measurement for acquiring ocular characteristics of the subject's eye E and photography for acquiring an image of the subject's eye E. The objective examination includes refractive power measurement (refractometry), corneal shape measurement (keratometry), intraocular pressure measurement, fundus photography, tomography (OCT photography) using optical coherence tomography (hereinafter, OCT: abbreviation for "Optical Coherence Tomography"), and measurement using OCT. In the subjective examination, a visual target or the like is presented to the subject, and information (ocular characteristics) about the subject's eye E is measured based on the subject's response to the presented visual target or the like. The subjective examination includes subjective refraction measurements such as a far-distance examination, an intermediate-distance examination, a near-distance examination, a contrast examination, and a glare examination, and a visual field examination.

[0014] The overall configuration of an ophthalmologic apparatus 100 according to the first embodiment will be described below with reference to FIG.

[0015] 1, the ophthalmologic apparatus 100 of the first embodiment includes a support base 110, a measurement unit 120, an examiner's controller 130, and a control unit 140. In the following, the left-right direction as viewed from the examinee is defined as the X direction, the up-down direction (vertical direction) is defined as the Y direction, and the direction perpendicular to the X direction and the Y direction (depth direction) is defined as the Z direction.

[0016] The support base 110 has a support column 111 standing up from the floor surface, and an optometry table 112 supported by the support column 111. The optometry table 112 is a platform on which devices and tools used in optometry, such as the examiner controller 130, are placed, and which supports the posture of the examinee. The optometry table 112 may have a fixed position in the Y direction (height position), or may be supported by the support column 111 so that the position in the Y direction (height position) is adjustable.

[0017] The measurement unit 120 has an arm 121, a measurement head 122, and a forehead rest 123. One end of the arm 121 is supported by the tip of the support 111, and the other end extends from the support 111 to the front side (subject side) along the Z direction, with the measurement head 122 attached to the tip. As a result, the measurement head 122 is suspended from the support 111 via the arm 121 above the optometry table 112. The arm 121 is movable in the Y direction relative to the support 111. The arm 121 may also be movable in the X direction or Z direction relative to the support 111.

[0018] The measurement head 122 is a part that measures the ocular characteristics of the subject's eye E. The measurement head 122 has a drive unit 122a and a pair of left and right measurement units 122L and 122R provided below the drive unit 122a. Here, the left measurement unit 122L and the right measurement unit 122R are paired to correspond to the left and right eyes of the subject, respectively.

[0019] The left measurement unit 122L includes a left measurement optical system 125L that presents a visual target to the subject's left eye E (hereinafter referred to as the "left eye") and measures the eye characteristics of the left eye with the visual target set to an arbitrary spherical power (corrective power). The right measurement unit 122R includes a right measurement optical system 125R that presents a visual target to the subject's right eye E (hereinafter referred to as the "right eye") and measures the eye characteristics of the right eye with the visual target set to an arbitrary spherical power (corrective power). The measurement results (objective measurement information) by the left measurement optical system 125L and the right measurement optical system 125R are input to the control unit 140. The detailed configurations of the left measurement optical system 125L and the right measurement optical system 125R will be described later.

[0020] The drive unit 122a is a mechanism that drives the left measurement unit 122L and the right measurement unit 122R individually to move horizontally (X direction), move vertically (Y direction), rotate in the X direction, and rotate in the Y direction.

[0021] The forehead rest 123 is provided in the measurement unit 120 and is disposed between the left measurement unit 122L and the right measurement unit 122R. The forehead rest 123 supports the subject's face by bringing part of the face (forehead) into contact with it during measurement of eye characteristics. That is, the subject facing the eye examination table 112 presses his / her forehead against the forehead rest 123 to stabilize the direction and position of the face. The position of the forehead rest 123 is adjusted by moving the arm 121 in the Y direction relative to the support 111.

[0022] The examiner's controller 130 is an information processing device that accepts an input operation by the examiner and outputs a control signal to the control unit 140. The examiner's controller 130 is, for example, a tablet terminal or a smartphone, and is separated from the measurement unit 120 and can be carried by the examiner. The examiner's controller 130 may be a notebook personal computer, a desktop personal computer, or a dedicated controller provided in the ophthalmic apparatus 100. The examiner's controller 130 exchanges information with the control unit 140 via wireless communication or network communication.

[0023] 1, the examiner's controller 130 includes an operation-side control unit (not shown), a display unit 131, and input buttons 132 (see FIG. 3). The display unit 131 is made up of a touch panel display provided on the surface of the examiner's controller 130, and the input buttons 132 are set by screen display. The operation-side control unit is made up of a microcomputer built into the examiner's controller 130. The operation-side control unit controls images to be displayed on the display unit 131 based on the measurement results and detection results transmitted from the control unit 140. The operation-side control unit also outputs a control signal to the control unit 140 in response to an operation on the input buttons 132.

[0024] The detailed configurations of the left measurement optical system 125L and the right measurement optical system 125R will be described below with reference to Fig. 2. Since the left measurement optical system 125L and the right measurement optical system 125R have the same configuration, in this specification, the description of the right measurement optical system 125R will be omitted and only the left measurement optical system 125L will be described.

[0025] The left measurement optical system 125L includes a Z alignment system 1, an XY alignment system 2, a keratometry system 3, a target projection system 4, an anterior segment observation system 5, a reflex measurement projection system 6, and a reflex measurement light receiving system 7 as an optical system for presenting a target to the subject's eye E (left subject's eye) to perform an examination. Hereinafter, the "fundus conjugate position" refers to a position that is optically approximately conjugate with the fundus Ef of the subject's eye E after the alignment is completed, and refers to a position that is optically conjugate with the fundus Ef of the subject's eye E or its vicinity. In addition, the "pupil conjugate position" refers to a position that is optically approximately conjugate with the pupil of the subject's eye E after the alignment is completed, and refers to a position that is optically conjugate with the pupil of the subject's eye E or its vicinity.

[0026] The anterior eye observation system 5 captures an image of the anterior eye of the subject's eye E. In the optical system passing through the anterior eye observation system 5, the imaging surface of the imaging element 59 is disposed at the pupil conjugate position Q. The anterior eye illumination light source 51 irradiates the anterior eye of the subject's eye E with illumination light (e.g., infrared light). The light reflected by the anterior eye of the subject's eye E passes through the objective lens 52, the dichroic mirror 53, the half mirror 54, the relay lens 55 and the relay lens 56, and the dichroic mirror 57. The light transmitted through the dichroic mirror 57 is imaged on the imaging surface of the imaging element 59 (area sensor) by the imaging lens 58. The imaging element 59 captures images and outputs signals at a predetermined rate. The output (video signal) of the imaging element 59 is input to the control unit 140. The control unit 140 causes the display unit 131 of the examiner's controller 130 to display an anterior eye image based on a video signal that is an output of the imaging element 59. The anterior eye image is, for example, an infrared moving image.

[0027] The Z alignment system 1 projects light (infrared light) for alignment in the optical axis direction (front-back direction, Z direction) of the anterior eye observation system 5 onto the subject's eye E. The light output from the Z alignment light source 11 is collimated by the projection lens 12 and projected onto the cornea of ​​the subject's eye E through an alignment hole formed in the keratoplasty plate 31. Based on the bright spot projected onto the cornea, the control unit 140 or the examiner controls the drive unit 122a so that the ratio between the interval between the two point images on the imaging element 59 by the Z alignment light source 11 and the diameter of the keratoplasty image falls within a predetermined range, and moves the left measurement optical system 125L in the Z direction.

[0028] The XY alignment system 2 irradiates the subject's eye E with light (infrared light) for performing alignment in directions (left-right direction (X direction) and up-down direction (Y direction)) perpendicular to the optical axis of the anterior eye observation system 5. The XY alignment system 2 includes an XY alignment light source 21 provided on an optical path branched off from the anterior eye observation system 5 by a half mirror 54, and a projection lens 22. The light output from the XY alignment light source 21 passes through the projection lens 22, is reflected by the half mirror 54, and is projected onto the subject's eye E via the anterior eye observation system 5. The light reflected by the cornea of ​​the subject's eye E is guided to an imaging element 59 via the anterior eye observation system 5.

[0029] The alignment method in each of the X, Y and Z directions is not limited to the method using the Z alignment system 1 and the XY alignment system 2. For example, any method capable of measuring the position of the subject's eye E using a stereo camera installed in the ophthalmic apparatus 100 may be used.

[0030] Here, the image based on the light reflected by the cornea (bright spot image) is included in the anterior eye image. The control unit 140 causes the display unit 131 to display the anterior eye image including the bright spot image and the alignment mark. When performing manual XY alignment, the examiner uses the examiner controller 130 to control the drive unit 122a so as to guide the bright spot image into the alignment mark, and moves the left measurement optical system 125L in the X and Y directions. When performing automatic XY alignment, the control unit 140 controls the drive unit 122a so as to cancel the displacement of the bright spot image relative to the alignment mark, and moves the left measurement optical system 125L in the X and Y directions.

[0031] The keratometry system 3 projects a ring-shaped light beam (infrared light) onto the cornea to measure the shape of the cornea of ​​the subject's eye E. The keratoplate 31 is disposed between the objective lens 52 and the subject's eye E. The keratoplate 31 is provided on the rear side (objective lens 52 side) of the keratoplate 31. The keratoplate 31 is illuminated with light from the keratoplate light source 32, so that a ring-shaped light beam is projected onto the cornea of ​​the subject's eye E. The reflected light (keratoplate image) from the cornea of ​​the subject's eye E is detected by the imaging element 59 together with the anterior segment image. The control unit 140 calculates corneal shape parameters that represent the shape of the cornea by performing a known calculation based on the keratoplate image.

[0032] The visual target projection system 4 is a visual target presenting unit that presents various visual targets, such as a fixation target and a visual target for subjective testing, to the subject's eye E. The visual target projection system 4 has a display 41, a half mirror 42, a relay lens 43, a reflecting mirror 44, a focusing lens 45, a relay lens 46, a field lens 47, a variable cross cylinder lens (VCC) 48, a reflecting mirror 49, and a dichroic mirror 68. The visual target projection system 4 also shares a dichroic mirror 53 and an objective lens 52 with the anterior eye observation system 5. Furthermore, the visual target projection system 4 has at least two glare light sources 41a that irradiate the subject's eye E with glare light at positions surrounding the optical axis on an optical path different from the optical path leading to the display 41 for subjective testing.

[0033] The light output from the display 41 is reflected by the half mirror 42, passes through the relay lens 43, is reflected by the reflecting mirror 44, and passes through the focusing lens 45. The light that passes through the focusing lens 45 passes through the relay lens 46, has its traveling direction aligned by the field lens 47, passes through the VCC 48, is reflected by the reflecting mirror 49, passes through the dichroic mirror 68, and is reflected by the dichroic mirror 53. The light reflected by the dichroic mirror 53 passes through the objective lens 52 and is projected onto the fundus Ef.

[0034] The display 41 displays a fixation target or a dot target as a target for fixing the gaze when performing an objective test or when fogging the subject's eye E, and displays a subjective test target for subjectively testing the eye characteristics (visual acuity value, distance vision power, near vision power, etc.) of the subject's eye E. The display 41 may be an organic EL (electroluminescence) display or a liquid crystal display (LCD), and is controlled by the control unit 140 to display any image. The display 41 is provided at a fundus conjugate position P on the optical path of the target projection system 4.

[0035] The focusing lens 45 is driven to advance and retreat in the optical axis direction by a drive motor (not shown) controlled by the control unit 140. The control unit 140 can displace the spherical power of the subject eye E to the minus diopter side by moving the focusing lens 45 toward the subject eye E. The control unit 140 can also displace the spherical power of the subject eye E to the plus diopter side by moving the focusing lens 45 in a direction away from the subject eye E. Furthermore, the control unit 140 can change the presentation position of the optotype displayed on the display 41 by driving the focusing lens 45 to advance and retreat, and can change the examination distance from the presentation position of the optotype to the subject eye E.

[0036] When a subjective test is performed, the control unit 140 moves the focusing lens 45 in the optical axis direction based on the result of the objective measurement, and controls the test distance and the spherical power of the test eye E. Then, the control unit 140 displays a predetermined optotype selected by the examiner or the control unit 140 on the display 41. This causes the optotype to be presented to the subject at a predetermined test distance for the test eye E adjusted to a predetermined spherical power. In addition, the subject may respond to the optotype, and the control unit 140 may receive the response content and perform further control or calculate the subjective test value. For example, in a visual acuity test, the control unit 140 selects and presents the next optotype based on the response to the Landolt ring or the like, and repeats this process to determine the visual acuity value.

[0037] The refraction measurement projection system 6 and the refraction measurement light receiving system 7 are objective measurement optical systems used for objective refraction measurement (refractometry) that objectively measures the refraction values ​​(refraction values), which are eye characteristics of the left and right eyes to be examined. The refraction measurement projection system 6 projects a ring-shaped light beam (infrared light) for objective measurement onto the fundus Ef. The refraction measurement light receiving system 7 receives the return light of this ring-shaped light beam from the eye E to be examined.

[0038] The reflex measurement light source 61 may be a SLD (Superluminescent Diode) light source, which is a high-brightness light source with a light emission diameter of a predetermined size or less. The reflex measurement light source 61 is movable in the optical axis direction and is arranged at a fundus conjugate position P. The ring diaphragm 65 (specifically, a light-transmitting portion) is arranged at a pupil conjugate position Q. The focusing lens 74 is movable in the optical axis direction. The focusing lens 74 may be a known variable focus lens whose focal position can be changed under the control of the control unit 140. In the optical system via the reflex measurement light receiving system 7, the imaging surface of the imaging element 59 is arranged at the fundus conjugate position P. The reflex measurement light source 61 and the focusing lens 74 can be moved in the optical axis direction in conjunction with each other. Furthermore, in the first embodiment, the reflex measurement light source 61 and the focusing lens 74 can be moved in the optical axis direction in conjunction with the focusing lens 45 of the visual target projection system 4.

[0039] The light output from the reflector measurement light source 61 passes through the relay lens 62 and enters the conical surface of the conical prism 63. The light that enters the conical surface is deflected and exits from the bottom surface of the conical prism 63. The light that exits from the bottom surface of the conical prism 63 passes through the field lens 64 and passes through a light-transmitting portion formed in a ring shape in the ring aperture 65. The light that passes through the light-transmitting portion of the ring aperture 65 (ring-shaped light beam) is reflected by the reflecting surface of the apertured prism 66, passes through the rotary prism 67, and is reflected by the dichroic mirror 68. The light reflected by the dichroic mirror 68 is reflected by the dichroic mirror 53, passes through the objective lens 52, and is projected onto the subject's eye E. The rotary prism 67 is used to average the light amount distribution of the ring-shaped light beam for the blood vessels and diseased parts of the fundus Ef and to reduce speckle noise caused by the light source.

[0040] It is desirable to place the conical prism 63 at a position as close to the pupil conjugate position Q as possible.

[0041] The field lens 64 may have, for example, a ring diaphragm 65 attached to the lens surface on the side of the subject's eye E. In this case, for example, a light-shielding film is evaporated onto the lens surface of the field lens 64 so that a ring-shaped light-transmitting portion is formed. The reflex measurement projection system 6 may have a configuration in which the field lens 64 is omitted.

[0042] The conical prism 63 may have, for example, a ring diaphragm 65 attached to the bottom surface facing the field lens 64. In this case, for example, a light-shielding film is evaporated onto the bottom surface of the conical prism 63 so as to form a ring-shaped light-transmitting portion. The ring diaphragm 65 may also be located on the conical surface side of the conical prism 63.

[0043] The ring diaphragm 65 may be a diaphragm having a light-transmitting portion formed with a shape corresponding to a predetermined measurement pattern. The diaphragm may have a light-transmitting portion formed at a position that is eccentric with respect to the optical axis of the reflector measurement projection system 6. The diaphragm may also have two or more light-transmitting portions formed.

[0044] The return light of the ring-shaped light beam projected on the fundus Ef passes through the objective lens 52 and is reflected by the dichroic mirror 53 and the dichroic mirror 68. The return light reflected by the dichroic mirror 68 passes through the rotary prism 67, passes through the hole of the aperture prism 66, passes through the relay lens 71, is reflected by the reflecting mirror 72, and passes through the relay lens 73 and the focusing lens 74. The light passing through the focusing lens 74 is reflected by the reflecting mirror 75, is reflected by the dichroic mirror 57, and is imaged on the imaging surface of the imaging element 59 by the imaging lens 58. The control unit 140 calculates the parameters of the eye refractive power by performing a known calculation based on the output from the imaging element 59. The parameters of the eye refractive power include the refraction value (refractive power), spherical power, cylindrical power, and cylindrical axis angle of the subject's eye E.

[0045] The control unit 140 is an information processing device provided below the optometry table 112. The control unit 140 comprehensively controls each part of the measurement unit 120 including the left measurement optical system 125L and the right measurement optical system 125R having the reflex measurement projection system 6, the reflex measurement light receiving system 7, the visual target projection system 4, etc., and the drive unit 122a, based on a control signal transmitted from the examiner's controller 130. In addition, the control unit 140 transmits the measurement result of the ocular characteristics of the subject's eye E measured by the measurement head 122 to the examiner's controller 130.

[0046] The control unit 140 includes a processor, and the functions of the processor are realized by circuits such as a central processing unit (CPU), a graphics processing unit (GPU), an application specific integrated circuit (ASIC), a programmable logic device (e.g., a simple programmable logic device (SPLD), a complex programmable logic device (CPLD), a field programmable gate array (FPGA)), etc. The control unit 140 realizes a desired function by, for example, reading and executing a program stored in a memory circuit or a storage device.

[0047] As shown in FIG. 3, the control unit 140 includes a main control unit 141, a storage unit 142, and a calculation processing unit 143.

[0048] The main controller 141 controls the Z alignment light source 11 of the Z alignment system 1, the XY alignment light source 21 of the XY alignment system 2, and the keratometry light source 32 of the keratometry system 3. This changes the amount of light output from the Z alignment light source 11, the XY alignment light source 21, and the keratometry light source 32, and switches them between on and off.

[0049] Furthermore, the main control unit 141 controls the display 41 of the visual target projection system 4. This allows the display of the visual target and fixation target shown on the display 41 to be turned on and off, and the visual target and fixation target to be switched.

[0050] The main controller 141 controls the anterior-eye illumination light source 51 and the image sensor 59 of the anterior-eye observation system 5. This changes the amount of light output from the anterior-eye illumination light source 51, and switches between on and off. It also changes the exposure time of the image sensor 59, and changes the detection sensitivity by controlling the gain of an amplifier included in the image sensor 59. A signal acquired by the image sensor 59 is input to the controller 140, and an image is formed by the arithmetic processor 143.

[0051] The main control unit 141 controls the reflex measurement light source 61 and the rotary prism 67 of the reflex measurement projection system 6, and the focusing lens 74 of the reflex measurement light receiving system 7. Thereby, the amount of light output from the reflex measurement light source 61 is changed, or the light is switched on or off. Also, the rotation speed of the rotary prism 67 is changed, or the rotation operation is switched on or off. Also, the position of the focusing lens 74 in the optical axis direction is changed. Also, the main control unit 141 can control a moving mechanism (not shown) that moves the reflex measurement light source 61 and the focusing lens 74 in the optical axis direction. Based on the calculated refraction value, the main control unit 141 moves the reflex measurement light source 61 and the focusing lens 74 in the optical axis direction, respectively, so that the fundus Ef, the reflex measurement light source 61, and the imaging surface of the imaging element 59 are optically conjugate. When the focusing lens 74 is a variable focus lens, the main control unit 141 can change the focal position of the focusing lens 74 by controlling the focusing lens 74.

[0052] In the ophthalmic apparatus 100 of the first embodiment, the main controller 141 controls a moving mechanism (not shown) that moves the focusing lens 45 of the visual target projection system 4. The moving mechanism is provided with an actuator that generates a driving force for the movement and a transmission mechanism that transmits the driving force. The actuator is, for example, a pulse motor. The transmission mechanism is, for example, a combination of gears or a rack-and-pinion. The main controller 141 can move the focusing lens 45 in the optical axis direction by controlling such a moving mechanism. The ophthalmic apparatus 100 changes the examination distance and the spherical power (correction power) of the left and right examinee's eyes E by moving the focusing lens 45 in the optical axis direction.

[0053] Furthermore, the main control unit 141 performs processing for writing data to the storage unit 142 and processing for reading data from the storage unit 142 .

[0054] Furthermore, the main controller 141 of the first embodiment performs an examination of the subject's eyes E, which includes presenting a fixation target to each of the left and right subject's eyes E after placing the left and right subject's eyes E in an anisometropic state, measuring the refraction values ​​of the left and right subject's eyes E while changing the examination distance from the fixation target to the left and right subject's eyes E within a predetermined distance range, and determining the fixating eye based on the measured refraction values. Note that the detailed procedure of the examination method will be described later.

[0055] The storage unit 142 stores various data. The data stored in the storage unit 142 include measurement information obtained by the keratometry system 3, measurement information obtained by the refraction measurement projection system 6 and the refraction measurement light receiving system 7, image data of an image acquired by the image sensor 59, and information on the subject's eye. The information on the subject's eye includes information on the subject such as a patient ID and name, and information on the subject's eye such as identification information of the left eye / right eye. The measurement information obtained by the keratometry system 3 is stored in the storage unit 142 when keratometry of the subject's eye E is performed by the ophthalmic device 100. The measurement information obtained by the refraction measurement projection system 6 and the refraction measurement light receiving system 7 is stored in the storage unit 142 when refractometry of the subject's eye E is performed by the ophthalmic device 100. The storage unit 142 may be used as a working memory for the calculation process of the corneal shape parameters of the subject's eye E and the calculation process of the refractive value. Moreover, the storage unit 142 stores various programs and data for operating the ophthalmologic apparatus 100.

[0056] The arithmetic processing unit 143 executes various calculations for obtaining parameters representing eye characteristics of the subject's eye E, such as corneal shape parameters and refractive power parameters. The arithmetic processing unit 143 of the first embodiment includes an analysis unit 144 and a fixation eye determination unit 145.

[0057] The analysis unit 144 analyzes a ring image (pattern image) obtained by the imaging element 59 receiving the return light of the ring-shaped light beam (ring-shaped measurement pattern) projected onto the fundus Ef by the reflex measurement projection system 6. For example, the analysis unit 144 obtains the center of gravity position of the ring image from the luminance distribution in the image in which the obtained ring image is depicted, obtains the luminance distribution along a plurality of scanning directions extending radially from the center of gravity position, and identifies the ring image from the luminance distribution. The analysis unit 144 can determine whether the luminance of the identified ring image (ring luminance) is within a predetermined luminance range. The analysis unit 144 may determine whether the S / N ratio of the identified ring image is within a predetermined numerical range.

[0058] The analysis unit 144 can obtain the spherical power, the cylindrical power, and the cylindrical axis angle by obtaining an approximation ellipse of the specified ring image and substituting the major axis and minor axis of the approximation ellipse into a known formula. The analysis unit 144 can also obtain the refraction value, the spherical power, the cylindrical power, and the cylindrical axis angle of the subject's eye E based on the specified ring image (approximation ellipse) and the control content (e.g., the amount of movement) of the focusing lens 74. Alternatively, the analysis unit 144 can obtain parameters of the eye refractive power, such as the refraction value of the subject's eye E, based on the deformation and displacement of the ring image relative to the reference pattern.

[0059] Furthermore, the analysis unit 144 calculates corneal shape parameters such as corneal refractive power, corneal astigmatism, and corneal astigmatism axis angle based on the keratinizing image acquired by the anterior eye observation system 5. For example, the analysis unit 144 calculates the corneal curvature radius of the principal meridian and the principal meridian of the anterior cornea by analyzing the keratinizing image, and calculates the corneal shape parameters based on the corneal curvature radius.

[0060] The fixing eye determination unit 145 determines the fixing eye based on the refractive value of the test eye E, which is the objective measurement information. Here, the "fixing eye" refers to the test eye E that, when viewing an object with both eyes, focuses the object on the fovea, captures the image, and actively looks at (fixates). Generally, if both the left and right test eyes E are maintained in a perfectly corrected state, both the left and right test eyes E will fixate, and both eyes will become the fixing eye. Also, if the left and right test eyes E are in an anisometropic state, one of the left and right test eyes E will become the fixing eye.

[0061] Moreover, the term "fully corrected state" refers to a state in which a fully corrected power, which is the power with the least stress that produces the best visual acuity, is prescribed and there is no subjective refractive error. The term "anisometropia state" refers to a state in which the left and right test eyes E have different deviations in refractive state from the target position, and in the first embodiment, one of the left and right test eyes E is maintained in a fully corrected state, and the spherical power of the other of the left and right test eyes E differs from the fully corrected state by a predetermined power (e.g., +2D (diopter)), resulting in a difference of a predetermined power (e.g., 2D) or more in the refractive values ​​(spherical powers) of the left and right test eyes E.

[0062] Specifically, the fixation eye determination unit 145 determines, for example, the subject's eye E that satisfies the following fixation eye conditions as a fixation eye. (1) A test eye E in which the difference between the refraction value corresponding to the position at which a fixation target is presented and the refraction value of the test eye itself when the fixation target is presented is equal to or less than a preset threshold value. (2) When the test distance from the fixation target to the test eye E is changed from far vision to near vision, of the left and right test eyes E, the test eye E whose own refraction value is closer to the refraction value corresponding to the presentation position of the fixation target (of the left and right test eyes E, the test eye E whose difference between the refraction value corresponding to the presentation position of the fixation target and the refraction value of the test eye itself has decreased more when the test distance is changed from far vision to near vision).

[0063] The procedure of the method for examining the subject's eye E performed using the ophthalmic apparatus 100 of the first embodiment will be described below with reference to the flowchart shown in FIG.

[0064] In step S1, the main control unit 141 (control unit 140) executes a "preliminary measurement" to acquire eye characteristics including the refractive values ​​of the left and right test eyes E based on the captured image of the ring image obtained by controlling the visual target projection system 4, the anterior eye observation system 5, the reflex measurement projection system 6, and the reflex measurement light receiving system 7, and proceeds to step S2. The main control unit 141 executes the preliminary measurement of step S1 two or more times, and the same type of measurement condition may be determined by each preliminary measurement so that the measurement condition converges each time the preliminary measurement is repeated, or different types of measurement condition may be determined. For example, in each preliminary measurement, at least one of the amount of light output from the reflex measurement light source 61 (the amount of light of the reflex measurement light source 61), the exposure time of the image sensor 59, the detection sensitivity of the image sensor 59, and the control content for the focusing lens 74 may be determined based on the obtained ring image.

[0065] In step S2, following the execution of the preliminary measurement in step S1, the main controller 141 executes a "main measurement" to measure a desired predetermined ocular characteristic (here, the refraction value of the eye E) under the measurement conditions determined by the last executed preliminary measurement, and proceeds to step S3. The refraction value of the eye E is measured in the following procedure. That is, the main controller 141 causes the refraction measurement projection system 6 to project a ring-shaped light beam (infrared light) for objective measurement onto the fundus Ef of the eye E. Then, the main controller 141 causes the refraction measurement light receiving system 7 to detect (receive) the return light of the ring-shaped light beam from the fundus Ef, and obtains the refraction value of the eye E by a well-known method based on the image signal from the image sensor 59. Note that steps S1 and S2 are objective examination processes.

[0066] In step S3, following the execution of the main measurement in step S2, the main controller 141 performs the start setting of the subjective test for each of the left and right test eyes E, and proceeds to step S4. Here, the "start setting of the subjective test" means adjusting the position of the focusing lens 45 in the target projection system 4 of the left measurement optical system 125L and the position of the focusing lens 45 in the target projection system 4 of the right measurement optical system 125R, respectively, so that the spherical power of each of the left and right test eyes E is in a perfect correction state at a predetermined far vision position (for example, test distance = zero D) based on the refractive value of the test eye E obtained in the main measurement. Note that "D (diopter)" is the reciprocal of the focal distance expressed in meters, so that "test distance = zero D" means that the test distance is infinite.

[0067] In step S4, following the setting of the start of the subjective test in step S3, the main control unit 141 executes the RG test using the RG chart. Here, the RG test is executed for each eye. The "RG chart" is, for example, a red icon with a visual target of numbers of different sizes and a ◎ mark and a ◯ mark of different sizes, and a green icon with a visual target of the same shape as the red icon, arranged side by side. The "RG test" refers to a test that uses the RG chart to subjectively check whether the correction state of the subject's eye E is in a perfect correction state (proper) (whether it is overcorrected or undercorrected) using a characteristic of light called chromatic aberration. Due to the characteristics of the ocular optic body, the shorter the wavelength of light, the greater the power at the refracting surface, so that the light of the green wavelength is imaged at a position shifted toward the incident side compared to the light of the red wavelength. Therefore, when the subject's eye E is in a state of undercorrection, the visual target is imaged in front of the retina, but the light of the red wavelength is imaged toward the rear, so the red visual target is clearly seen. When the subject's eye E is in a perfect correction state, the green and red optotypes are seen approximately equally. Furthermore, when the subject's eye E is in an overcorrected state, the green optotype is seen more clearly. In the first embodiment, the position of the focusing lens 45 is changed to adjust the spherical power (correction power) of the subject's eye E until the subject sees the green and red optotypes on the RG chart evenly, that is, until the perfect correction state of the left and right subject's eyes E can be confirmed. As a result, the left and right subject's eyes E are prescribed perfect correction values.

[0068] In step S5, following the execution of the RG test in step S4 or the determination that the test distance is not equal to the predetermined distance in step S6, the main controller 141 adjusts the position of the focusing lens 45 to present fixation targets (left fixation target 500L and right fixation target 500R described later) at a predetermined far-vision position (for example, test distance=zero D) for each of the left and right test eyes E. Furthermore, the main controller 141 moves the focusing lens 45 in the optical axis direction while presenting the fixation targets (left fixation target 500L and right fixation target 500R), changing the presentation position of the fixation targets (left fixation target 500L and right fixation target 500R) to the near-vision direction by the same amount for both the left and right, and proceeds to step S6. As a result, the test distance becomes shorter with the perfect correction value for far vision prescribed. In the first embodiment, the main controller 141 continuously changes the presentation position while presenting the fixation targets.

[0069] Here, different fixation targets are presented to the left and right test eyes E. That is, the left fixation target 500L shown in Fig. 5A is presented to the left test eye by the target projection system 4 (light-projecting optical system for the left eye) of the left measurement optical system 125L. Also, the right fixation target 500R shown in Fig. 5B is presented to the right test eye by the target projection system 4 (light-projecting optical system for the right eye) of the right measurement optical system 125R.

[0070] The left fixation target 500L includes a background target 501L, a fusion target 502L, and a test target 503L. The background target 501L is a target displayed in the entire target presentation area, for example, and the fusion target 502L and the test target 503L are superimposed. The background target 501L is shown here as a white rectangle. The fusion target 502L is a target that can be fused when the left test eye visually recognizes the left fixation target 500L and the right test eye visually recognizes the right fixation target 500R, and is displayed in black at the center of the background target 501L. The test target 503L is a target that cannot be fused when the left test eye visually recognizes the left fixation target 500L and the right test eye visually recognizes the right fixation target 500R, and is displayed in black below the fusion target 502L.

[0071] The right fixation target 500R includes a background target 501R, a fusion target 502R, and a test target 503R. The background target 501R is, for example, a target displayed in the entire target presentation area, and the fusion target 502R and the test target 503R are superimposed. The background target 501R is shown here as a white rectangle. The fusion target 502R is a target that can be fused when the left fixation target 500L is viewed with the left eye and the right fixation target 500R is viewed with the right eye, and is displayed in black at the center of the background target 501R. The test target 503R is a target that cannot be fused when the left fixation target 500L is viewed with the left eye and the right fixation target 500R is viewed with the right eye, and is displayed in black above the fusion target 502R.

[0072] When the left fixation target 500L is viewed with the left eye and the right fixation target 500R is viewed with the right eye, if the left fixation target 500L and the right fixation target 500R are fused, the subject will see the background targets 501L and 501R and the fusion targets 502L and 502R as one, and the test targets 503L and 503R will be viewed above and below the fusion targets 502L and 502R, respectively, as shown in Fig. 5C. If the left fixation target 500L and the right fixation target 500R are not fused, the main control unit 141 may stop the examination of the subject's eye E shown in Fig. 4, or may output an alert to select continuation of the examination.

[0073] In step S6, following the presentation of the fixation target and the change of the target position in step S5, the main controller 141 judges whether the test distance, which is the distance from the subject's eye E to the fixation target (left fixation target 500L, right fixation target 500R), reaches a preset predetermined distance. If the main controller 141 judges YES (test distance = predetermined distance), it proceeds to step S7, and if it judges NO (test distance ≠ predetermined distance), it returns to step S5. Here, the "predetermined distance" can be set arbitrarily, but is set to 4D in the first embodiment.

[0074] As a result, the ophthalmologic apparatus 100 of Example 1 can present fixation targets (left fixation target 500L, right fixation target 500R) to the left and right test eyes E in a perfectly corrected state, and can change the examination distance (presentation position of the fixation targets (left fixation target 500L, right fixation target 500R)) within a predetermined distance range (zero D to 4D).

[0075] In step S7, following the determination in step S6 that the test distance is equal to the specified distance or the determination in step S15 that the binocular test has not been completed, the main control unit 141 moves the focusing lens 45 in the optical axis direction to adjust the spherical power of each of the left and right test eyes E to a fully corrected state again, and proceeds to step S8.

[0076] In step S8, following the adjustment of the spherical power in step S7, the position of the focusing lens 45 is adjusted, and fixation targets (left fixation target 500L and right fixation target 500R described later) are presented at a predetermined distance position (for example, test distance = zero D) for each of the left and right test eyes E. Furthermore, the main control unit 141 moves the focusing lens 45 facing one test eye E in the optical axis direction, changes the spherical power of one test eye E by a predetermined power (for example, +2D addition) with respect to the power of the fully corrected state in far vision, and proceeds to step S9. At this time, the focusing lens 45 facing the other test eye E does not move, and the spherical power of the other test eye E is maintained in the fully corrected state set in step S7. As a result, of the left and right test eyes E, one test eye E is in a corrected state of a predetermined power (for example, 2D), and the spherical power of the other test eye E is in a fully corrected state, and a prescription for anisometropia has been made. The subject's eye E whose spherical power is changed in step S8 is the subject's eye E whose spherical power has never been changed from the perfectly corrected state during the examination shown in FIG.

[0077] In step S9, following the change in the spherical power of one eye in step S8 or the determination that the test distance has changed by the subjective test distance in step S11, the examiner asks the subject how the test optotypes 503L and 503R look (which of the test optotypes 503L and 503R is clearly visible), and the process proceeds to step S10. The examiner can determine the fixation eye based on the subject's answer. The subject's answer may also be input to the fixation eye determination unit 145 of the control unit 140. The main control unit 141 temporarily stops changing the optotype position at the timing when it is determined that the test distance has changed by the subjective test distance. Then, the main control unit 141 fixes the presentation position of the fixation target from the time the examiner asks the question until the subject's answer is obtained, and after the subject's answer is obtained, the main control unit 141 changes the optotype position again to the near vision direction based on the input of the subject's answer or the examiner's instruction.

[0078] In step S10, following the question to the subject in step S9 or the determination that the test distance is not equal to the predetermined distance in step S12, the main controller 141 moves the focusing lens 45 in the optical axis direction to change the presentation positions of the fixation targets (left fixation target 500L, right fixation target 500R) presented to the left and right eyes E to the near vision direction by the same amount, and proceeds to step S11. As a result, the test distance becomes shorter with the prescription for anisometropia being performed. In the first embodiment, the main controller 141 continuously changes the presentation positions while the fixation targets are presented.

[0079] In step S11, following the change in the target position in step S10, the main controller 141 judges whether the test distance has changed by a preset subjective test distance. If the main controller 141 judges YES (test distance = change by subjective test distance), the process returns to step S9, and if the main controller 141 judges NO (test distance ≠ change by subjective test distance), the process proceeds to step S12. The "subjective test distance" can be set arbitrarily, but is set to +1D here.

[0080] In step S12, following the determination in step S11 that the test distance has not changed by the subjective test distance, the main controller 141 determines whether the test distance has reached a preset predetermined distance. If the main controller 141 determines YES (test distance=predetermined distance), the process proceeds to step S13, and if the main controller 141 determines NO (test distance≠predetermined distance), the process returns to step S10. Note that the "predetermined distance" can be set arbitrarily, but is set to 4D in the first embodiment.

[0081] As a result, in the ophthalmologic apparatus 100 of Example 1, fixation targets (left fixation target 500L, right fixation target 500R) are presented to the left and right test eyes E in a state of anisometropia, and the test distance can be changed within a predetermined distance range (zero D to 4 D) while asking the patient how the test targets 503L and 503R appear each time the test distance changes by +1 D.

[0082] In step S13, following the determination that the test distance is equal to the predetermined distance in step S12, the fixation eye determination unit 145 determines the fixation eye based on the refraction value of the test eye E, and proceeds to step S14. That is, the fixation eye determination unit 145 monitors the refraction values ​​of the left and right test eyes E from the presentation of the fixation target in the perfect correction state and the change of the target position in step S5 to the determination that the test distance is equal to the predetermined distance in step S12. Then, the fixation eye determination unit 145 compares the refraction value according to the presentation position of the fixation target with the refraction values ​​of the left and right test eyes E, respectively, and determines the test eye E that satisfies the preset fixation eye condition as a fixation eye, and determines the test eye E that does not satisfy the fixation eye condition as a non-fixation eye. The fixation eye determination unit 145 may determine the fixation eye at the timing when the test distance reaches the predetermined subjective test distance, or may continuously determine the fixation eye while the test distance is being changed. When determining the fixation eye, the fixation eye determination section 145 may take into consideration the answer to the question posed to the subject in step S9 (the result of the subjective test).

[0083] In step S14, following the determination of the fixation eye in step S13, the main controller 141 determines whether or not a fixation alternation occurs while the test distance changes within a predetermined distance range (0D to 4D) based on the result of the fixation eye determination in step S13, and proceeds to step S15. Note that "fixation alternation" refers to a change in the fixation eye while the test distance changes.

[0084] In step S15, following the determination of fixation alternation in step S14, the main controller 141 determines whether the examination of the left and right subject eyes E has been completed. If the main controller 141 determines YES (binocular examination completed), it proceeds to END, and if it determines NO (binocular examination not completed), it proceeds to step S7. In step S15, if the change in spherical power in step S8 has been made for both the left and right subject eyes E, it is determined that the examination of the left and right subject eyes E has been completed. In addition, in step S15, if the change in spherical power in step S8 has been made for only one of the left and right subject eyes E, it is determined that the examination of the left and right subject eyes E has not been completed (binocular examination not completed).

[0085] In step S16, the main controller 141 controls the refraction measurement projection system 6 and the refraction measurement light receiving system 7 to perform refraction measurement (measurement of refraction value) of the left and right test eyes E, and proceeds to step S17. Here, the refraction measurement is performed in real time in a time series in parallel with the change of the test distance during the period from the change of the target position after the RG test (step S5) to the determination of whether the test distance is equal to the predetermined distance (step S12). Note that the refraction measurement may be performed continuously or intermittently at any timing during the period from the change of the target position after the RG test (step S5) to the determination of whether the test distance is equal to the predetermined distance (step S12).

[0086] As a result, the main controller 141 acquires the refraction values ​​(REF values) of the left and right eyes E to be examined as objective measurement information. The main controller 141 may acquire the objective measurement information (REF values) intermittently at the timing when the test distance reaches a predetermined distance (for example, the timing when the test distance changes by the subjective test distance (for example, +1D)). In this case, the main controller 141 may temporarily stop changing the test distance while acquiring the objective measurement information, that is, while measuring the refraction values. The main controller 141 may also continuously acquire the objective measurement information (REF values) while the test distance is changed within a predetermined distance range (0D to 4D).

[0087] In step S17, following the refractometry in step S16, the main control unit 141 outputs a command to the examiner's controller 130 to display the objective measurement information (refractive value) on the display unit 131 at a predetermined timing. As a result, the objective measurement information (refractive value) is displayed on the display unit 131 at a predetermined timing. Here, the objective measurement information displayed on the display unit 131 is, for example, information that represents the relationship between the refraction values ​​of the left and right examinee's eyes E and the test distance in a two-dimensional coordinate graph (see Figs. 6A to 8C). In addition, the "predetermined timing" may be, for example, the timing when the test distance changes by the subjective test distance (for example, +1D), or the refraction value may be displayed in real time each time the measurement is performed. In addition, the refraction value to be displayed may be a value obtained at the time of display, or may be an average value of values ​​obtained during a time interval.

[0088] The operation of the ophthalmologic apparatus 100 of the first embodiment will be described as follows.

[0089] After performing a preliminary measurement (step S1) and a main measurement (step S2), the ophthalmic device 100 of the first embodiment first adjusts the spherical power so that the left and right test eyes E are each in a perfect correction state (steps S3 and S4). Next, the ophthalmic device 100 of the first embodiment brings the left and right test eyes E into a perfect correction state, and presents a left fixation target 500L to the left test eye and a right fixation target 500R to the right test eye while changing the test distance within a predetermined distance range (0D to 4D). Then, the ophthalmic device 100 of the first embodiment measures the refractive values ​​of the left and right test eyes E that are binocularly viewing the fixation targets (left fixation target 500L, right fixation target 500R), and acquires objective measurement information (steps S5, S6, S16, and S17: third step).

[0090] That is, the ophthalmic device 100 of the first embodiment presents fixation targets (left fixation target 500L, right fixation target 500R) at a predetermined far-vision position (test distance=zero D) for each of the left and right test eyes E in a perfectly corrected state, and further changes the presentation position of the fixation targets (left fixation target 500L, right fixation target 500R) to the near-vision direction while the fixation targets (left fixation target 500L, right fixation target 500R) are still presented. Then, the ophthalmic device 100 of the first embodiment measures the refraction value of the test eye E viewing the fixation targets (left fixation target 500L, right fixation target 500R). In the first embodiment, the change of the test distance is temporarily stopped every time the test distance increases by +1D from the state of zero D until the test distance reaches 4D (every time the test distance reaches zero D, 1D, 2D, 3D, and 4D), and the refraction values ​​of the left and right test eyes E are acquired.

[0091] Here, the amount of accommodation response of each subject eye E can be known from the amount of change in refraction value accompanying a change in the test distance. Therefore, the ophthalmic device 100 of the first embodiment measures the amount of accommodation response of the left and right subject eyes E in a binocular perfect correction state by objectively acquiring refraction values ​​at test distances of 0 D, 1 D, 2 D, 3 D, and 4 D in a binocular perfect correction state.

[0092] Next, the ophthalmic device 100 of the first embodiment adjusts the spherical power of each of the right and left examinee eyes E to a perfect correction state (step S7), and then maintains one (here, the left) examinee eye E in the perfect correction state, changes the spherical power of the other (here, the right) examinee eye E by a predetermined power (+2D addition) relative to the power of the perfect correction state, and prescribes anisometropia with +2D addition only for the right examinee eye (step S8). This reproduces a monovision state in which the left examinee eye is corrected to see distant objects and the right examinee eye is corrected to see close objects.

[0093] Then, the ophthalmologic apparatus 100 of the first embodiment presents a left fixation target 500L to the left eye to be examined and a right fixation target 500R to the right eye to be examined while changing the examination distance within a predetermined distance range (0D to 4D) in a state where an anisometropia of +2D is prescribed for the right eye to be examined. Then, the ophthalmologic apparatus 100 of the first embodiment measures the refractive values ​​of the left and right eyes E to be examined that are binocularly viewing the fixation targets (left fixation target 500L, right fixation target 500R), and acquires objective measurement information (steps S10, S11, S12, S16, and S17: first step).

[0094] That is, the ophthalmic device 100 of the first embodiment presents fixation targets (left fixation target 500L, right fixation target 500R) at a predetermined far-vision position (test distance=zero D) for each of the left and right test eyes E in an anisometropic state with +2D added to the right test eye, and further changes the presentation positions of the fixation targets (left fixation target 500L, right fixation target 500R) to the near-vision direction while still presenting the fixation targets (left fixation target 500L, right fixation target 500R).Then, the ophthalmic device 100 of the first embodiment measures the refractive value of the test eye E viewing the fixation targets (left fixation target 500L, right fixation target 500R). In the first embodiment, each time the test distance increases by +1D from zero D to 4D (each time the test distance reaches zero D, 1D, 2D, 3D, and 4D), the change in the test distance is temporarily stopped and the refraction values ​​of the left and right test eyes E are acquired. Also, in the first embodiment, the examiner checks the visibility of the left and right test targets 503L and 503R (subjective test) each time the test distance increases by a predetermined subjective test distance (+1D) from zero D to 4D (each time the test distance reaches zero D, 1D, 2D, 3D, and 4D) (step S9).

[0095] Therefore, the ophthalmologic apparatus 100 of the first embodiment measures the amount of accommodation response of the left and right test eyes E in a state of anisometropia in which +2D is added to only the right test eye from a state of complete binocular correction, and also allows the user to confirm how the fixation target appears at specified test distances (zero D, 1D, 2D, 3D, 4D).

[0096] Furthermore, the ophthalmic device 100 of the first embodiment measures the refraction value, and then, based on the measured refraction value, judges the fixed eye when the test distance reaches a predetermined subjective test distance (zero D, 1D, 2D, 3D, 4D) in the anisometropic state in which +2D is added to the right eye to be examined (step S13). Then, based on the result of the determination of the fixed eye, the ophthalmic device 100 of the first embodiment judges whether or not a fixation alternation occurs while the test distance changes in the anisometropic state in which +2D is added to the right eye to be examined (step S14). The result of the determination of the fixed eye and the result of the determination of the presence or absence of fixation alternation are appropriately displayed on the display unit 131.

[0097] Furthermore, after the determination of fixation alternation in the anisometropic state with +2D added to the right eye is completed, the ophthalmic device 100 of the first embodiment adjusts the spherical power of the right and left eyes E to a fully corrected state (step S7), and then, while maintaining the other eye E (here, the right eye) in the fully corrected state, changes the spherical power of one eye E (here, the left eye) by a predetermined power (+2D added) with respect to the power in the fully corrected state, and prescribes anisometropia with +2D added only to the left eye (step S8). This reproduces a monovision state in which the right eye is corrected to see far away and the left eye is corrected to see close up.

[0098] Then, the ophthalmologic apparatus 100 of the first embodiment presents a left fixation target 500L to the left eye to be examined and a right fixation target 500R to the right eye to be examined while changing the examination distance within a predetermined distance range (0D to 4D) in a state where an anisometropia of +2D is prescribed for the left eye to be examined. Then, the ophthalmologic apparatus 100 of the first embodiment measures the refractive values ​​of the left and right eyes E to be examined that are binocularly viewing the fixation targets (left fixation target 500L, right fixation target 500R), and acquires objective measurement information (steps S10, S11, S12, S16, and S17: second step).

[0099] That is, the ophthalmologic apparatus 100 of the first embodiment presents fixation targets (left fixation target 500L, right fixation target 500R) at a predetermined far-vision position (test distance=zero D) for each of the left and right test eyes E in an anisometropic state with +2D added to the left test eye, and further changes the presentation positions of the fixation targets (left fixation target 500L, right fixation target 500R) to the near-vision direction while still presenting the fixation targets (left fixation target 500L, right fixation target 500R).Then, the ophthalmologic apparatus 100 of the first embodiment measures the refractive value of the test eye E viewing the fixation targets (left fixation target 500L, right fixation target 500R). In the first embodiment, each time the test distance increases by +1D from zero D to 4D (each time the test distance reaches zero D, 1D, 2D, 3D, and 4D), the change in the test distance is temporarily stopped and the refraction values ​​of the left and right test eyes E are acquired. Also, in the first embodiment, the examiner checks the visibility of the left and right test targets 503L and 503R (subjective test) each time the test distance increases by a predetermined subjective test distance (+1D) from zero D to 4D (each time the test distance reaches zero D, 1D, 2D, 3D, and 4D) (step S9).

[0100] Therefore, the ophthalmologic apparatus 100 of Example 1 measures the amount of accommodation response of both the left and right test eyes E even in a state of anisometropia in which +2D is added to only the left test eye from a state of complete binocular correction, and allows the user to confirm how the fixation target appears at specified test distances (zero D, 1D, 2D, 3D, 4D).

[0101] Furthermore, the ophthalmologic apparatus 100 of the first embodiment measures the refraction value, and then, based on the measured refraction value, judges the fixed eye when the test distance reaches a predetermined subjective test distance (zero D, 1D, 2D, 3D, 4D) in the anisometropic state in which +2D is added to the left eye to be examined (step S13). Then, based on the result of the fixation eye judgment, the ophthalmologic apparatus 100 of the first embodiment judges whether or not a fixation alternation occurs while the test distance changes in the anisometropic state in which +2D is added to the left eye to be examined (step S14). The result of the fixation eye judgment and the result of the fixation alternation judgment are appropriately displayed on the display unit 131.

[0102] Then, when the ophthalmologic apparatus 100 of Example 1 adds +2D alternately to the left and right test eyes E to create an anisometropic state and measures the amount of accommodation response (when YES is determined in step S15), it terminates the examination of the test eye E shown in Figure 4.

[0103] In this way, in the ophthalmologic apparatus 100 of the first embodiment, when one of the left and right test eyes E is maintained in a perfectly corrected state and the other of the left and right test eyes E is prescribed to have anisometropia corrected by a predetermined degree from the perfectly corrected state, the target projection system 4 presents the fixation targets (left fixation target 500L, right fixation target 500R) while changing the test distance from the left and right test eyes E to the fixation targets (left fixation target 500L, right fixation target 500R) within a predetermined distance range (0D to 4D). Then, the control unit 140 measures the refractive value of the eye when the fixation targets (left fixation target 500L, right fixation target 500R) are viewed with both eyes by the refraction measurement projection system 6 and the refraction measurement light receiving system 7, and obtains the refractive values ​​of the left and right test eyes E as objective measurement information.

[0104] Here, the refraction value of the fixating eye and the refraction value of the non-fixating eye have different amounts of separation and variation with respect to the reference refraction value according to the presentation position of the fixation target. Therefore, the ophthalmic device 100 of the first embodiment can obtain the refraction values ​​of the left and right test eyes E while varying the test distance, allowing the examiner to distinguish the fixating eye for each test distance in the anisometropic state. Then, the examiner can use the ophthalmic device 100 of the embodiment to evaluate the relationship between the subjective appearance of the fixation target and the refraction value (accommodation state) for each predetermined test distance (zero D, 1D, 2D, 3D, 4D) when the monovision state is reproduced.

[0105] Moreover, the ophthalmologic apparatus 100 of the first embodiment reproduces the monovision state, allowing the examiner to check whether or not the subject's accommodation at near vision is reduced. Furthermore, the examiner can evaluate the subject's adaptability to monovision based on the difference in the amount of accommodation reaction and the presence or absence of reduction in accommodation at near vision.

[0106] In addition, in the first embodiment, since the fixating eye for each test distance in an anisometropic state can be identified by using the ophthalmic device 100, the examiner can perform monovision training during the test. Note that the monovision training is to make the examinee feel a sensation of being able to see a wide range from far to near without adjusting by switching the fixating eye, for example, by encouraging the examinee to look at a fixation target with the examinee's eye E having a larger spherical power addition, or encouraging the examinee to look at a distant object with the examinee's eye E having a larger spherical power addition.

[0107] Furthermore, the ophthalmologic apparatus 100 of the first embodiment has an anterior eye observation system 5, and presents fixation targets (left fixation target 500L, right fixation target 500R) to the left and right test eyes E, respectively, and acquires anterior eye images in a fused state, so that it is possible to measure the eye positions (gaze directions) of the left and right test eyes E. To detect the left gaze direction as a reference for the left test eye and the right gaze direction as a reference for the right test eye, the main controller 141 first obtains two-dimensional positions of the pupil center positions of the left test eye and the right test eye based on the anterior eye images and magnification of the left test eye and the right test eye. Next, the main controller 141 obtains a reference position, which is a two-dimensional position of a bright spot (bright spot image Br) drawn by the XY alignment system 2, based on the anterior eye images and magnification of the left test eye and the right test eye. Then, the main controller 141 obtains the left gaze direction and the right gaze direction based on the reference position and the pupil center position. The method for determining the left and right gaze directions is not limited to the above method, and other well-known methods may be used.

[0108] In addition, when the left and right gaze directions are detected, if there is a large difference between the convergence distance calculated from the convergence angle obtained from the detected gaze direction and the convergence distance set by controlling the drive unit 122a, or if the subject complains that the fusion target appears double, it is possible that the target is not viewed with both eyes (not fused). For this reason, the examiner or the main control unit 141 may prompt the subject to turn his or her gaze in the direction of the target and re-detect the left and right gaze directions.

[0109] In the ophthalmic device 100 of the first embodiment, the main controller 141 may temporarily stop changing the examination distance when the examination distance reaches a predetermined distance (for example, zero D, 1D, 2D, 3D, or 4D) and then intermittently acquire objective measurement information (refractive value). In this case, the ophthalmic device 100 of the first embodiment can reduce the computation load of the refraction value.

[0110] In the ophthalmic apparatus 100 of the first embodiment, the main control unit 141 may continuously obtain objective measurement information (refractive value) while the examination distance is changed within a predetermined distance range (for example, 0D to 4D). In this case, the ophthalmic apparatus 100 of the first embodiment allows the examiner to continuously grasp the fluctuation of the refractive value of the subject's eye E accompanying the change of the examination distance. Therefore, the examiner can recognize the change of the refractive value in detail, and can grasp the occurrence timing of the fixation alternation more accurately. In addition, the ophthalmic apparatus 100 may display in real time which eye of the left and right subjects' eyes E is automatically determined to be the fixating eye. Thereby, the ophthalmic apparatus 100 of the first embodiment can further make it easier to understand the occurrence timing of the fixation eye alternation.

[0111] The ophthalmologic apparatus 100 of the first embodiment is controlled by the control unit 140 and includes a target projection system 4 (a light-projecting optical system for the left eye) of the left measurement optical system 125L that presents a left fixation target 500L to the left eye to be examined, and a target projection system 4 (a light-projecting optical system for the right eye) of the right measurement optical system 125R that presents a right fixation target 500R to the right eye to be examined. The control unit 140 adjusts the spherical powers of the left and right eyes E to perform a prescription for anisometropia by moving the focusing lens 45 of the target projection system 4 in the left measurement optical system 125L and the focusing lens 45 of the target projection system 4 in the right measurement optical system 125R in the optical axis direction, respectively.

[0112] As a result, the ophthalmic device 100 of Example 1 can integrally have a correction function for adjusting the spherical power of the test eye E, a target presentation function for presenting fixation targets individually to the left and right test eyes E, and an objective measurement function for objectively measuring the ocular characteristics of the test eye E.

[0113] In the ophthalmologic apparatus 100 of the first embodiment, the left fixation target 500L includes a fusion target 502L that can be fused when the left eye to be examined views the left fixation target 500L and the right eye to be examined views the right fixation target 500R, and a test target 503L that cannot be fused when the left eye to be examined views the left fixation target 500L and the right eye to be examined views the right fixation target 500R. The right fixation target 500R includes a fusion target 502R that can be fused when the left eye to be examined views the left fixation target 500L and the right eye to be examined views the right fixation target 500R, and a test target 503R that cannot be fused when the left eye to be examined views the left fixation target 500L and the right eye to be examined views the right fixation target 500R.

[0114] In this way, the ophthalmologic apparatus 100 of the first embodiment allows the subject to check how the test targets 503L and 503R look, and to perform a subjective test to check the fixating eye. That is, the examiner can determine the fixating eye based on the subjective test.

[0115] In the ophthalmologic apparatus 100 of the first embodiment, the control unit 140 includes a fixation eye determination unit 145 that determines a fixation eye based on the objective measurement information (refractive value).

[0116] Therefore, the ophthalmologic apparatus 100 of the first embodiment can mechanically determine the fixating eye for each test distance, and the examiner can easily recognize the fixating eye for each test distance in an anisometropic state.

[0117] Furthermore, in the ophthalmologic apparatus 100 of the first embodiment, the fixed eye determination unit 145 determines the subject's eye E that satisfies any one of the following fixed eye conditions as a fixed eye. (1) A test eye E in which the difference between the refraction value corresponding to the position at which a fixation target is presented and the refraction value of the test eye itself when the fixation target is presented is equal to or less than a preset threshold value. (2) When the test distance from the fixation target to the test eye E is changed from far vision to near vision, of the left and right test eyes E, the test eye E whose own refraction value is closer to the refraction value corresponding to the presentation position of the fixation target (of the left and right test eyes E, the test eye E whose difference between the refraction value corresponding to the presentation position of the fixation target and the refraction value of the test eye itself has decreased more when the test distance is changed from far vision to near vision).

[0118] Thereby, the ophthalmologic apparatus 100 of the first embodiment can perform accurate determination when mechanically determining the fixating eye.

[0119] The examination method of Example 1 includes a first step of maintaining the left test eye in a perfectly corrected state, prescribing the right test eye to have anisometropia with +2D added, presenting a fixation target, changing the test distance within a predetermined distance range (zero D to 4D), and acquiring the refractive values ​​of the left and right test eyes E as objective measurement information; and a second step of, after acquiring the objective measurement information in the first step, maintaining the right test eye in a perfectly corrected state, prescribing the left test eye to have anisometropia with +2D added, presenting a fixation target, changing the test distance within a predetermined distance range (zero D to 4D), and acquiring the refractive values ​​of the left and right test eyes E as objective measurement information.

[0120] Therefore, the examination method of the first embodiment allows the examiner to recognize the fixation eye for each test distance in the anisometropia state in which +2D is added to the right eye to be examined and the fixation eye for each test distance in the anisometropia state in which +2D is added to the left eye to be examined, respectively. This allows the examiner to more accurately evaluate the suitability of the examinee for monovision.

[0121] In addition, the examination method of Example 1 includes a third step in which, before obtaining objective measurement information (refractive values) in a state of anisometropia in the first step, a prescription is made to bring both the left and right test eyes E into a state of complete correction, a fixation target is presented, and the examination distance is changed within a predetermined distance range (zero D to 4 D), and the refractive values ​​of the left and right test eyes E are obtained as objective measurement information.

[0122] Therefore, the test method of Example 1 can measure the refractive values ​​of the left and right test eyes E for each test distance in both the binocular complete correction state and the anisometropia state. Then, the examiner can evaluate whether there is a difference in the accommodation response amount of the test eye E when the binocular complete correction state is set and when the monovision state is reproduced. In addition, the test method of Example 1 can confirm whether the change of the fixation eye is due to the insufficient capacity of the accommodation response amount of the eye, or whether the fixation eye changes despite the ability to accommodate.

[0123] In the following, the relationship between the test distance (zero D to 4D) and the refraction value in each state of "binocular complete correction state", "right eye + 2D added anisometropia state", and "left eye + 2D added anisometropia state" for the first, second and third subjects will be described with reference to Figs. 6A to 8C. In addition, the right eye is the dominant eye for all of the first to third subjects. The "dominant eye" is the eye that is predominantly recognized as the visual information transmitted to the brain when viewing with both eyes. In addition, the results shown in Figs. 6A to 8C are shown by connecting the refraction values ​​measured at the timing when the visual target position is changed with a straight line. However, the refraction value may be continuously measured while the visual target position is changed. In this case, the result of the refraction value is a continuous result. In addition, the refraction value may be measured multiple times at the timing when the visual target position is changed, and the multiple results may be averaged to obtain the refraction value at the visual target position.

[0124] 6A to 6C show the results of the first subject. In the first subject, when both the left and right eyes E are in a perfect correction state, as shown in FIG. 6A, the difference between the refraction value of the left eye shown by the dashed line and the refraction value of the right eye shown by the solid line, and the refraction value according to the presentation position of the fixation target (left fixation target 500L, right fixation target 500R) shown by the dashed and dotted line, is below a preset threshold value (e.g., 0.5D) regardless of the test distance. Therefore, in the first subject, if both the left and right eyes are in a perfect correction state, it is determined that the left and right eyes E are fixated regardless of the test distance.

[0125] In contrast, in the first subject, in the anisometropic state with +2D added to the right eye, the difference between the refraction value according to the fixation target presentation position and the refraction value of the left eye is about 0D to 0.5D (below the threshold) regardless of the test distance, as shown in FIG. 6B, and the difference between the refraction value according to the fixation target presentation position and the refraction value of the right eye is about 1.8D to 2D (above the threshold). In the subjective test, in the anisometropic state with +2D added to the right eye, the first subject answered that the test target 503L of the left fixation target 500L is easy to see regardless of the test distance. Therefore, in the anisometropic state with +2D added to the right eye, the first subject is determined to have the left eye as the fixed eye regardless of the test distance, and is determined to have no fixation alternation.

[0126] In addition, in the first subject, in the anisometropic state in which +2D is added to the left eye, the difference between the refraction value according to the presentation position of the fixation target and the refraction value of the right eye is about 0D to 0.4D (below the threshold) regardless of the test distance, as shown in FIG. 6C, and the difference between the refraction value according to the presentation position of the fixation target and the refraction value of the left eye is about 1.5D to 2D (above the threshold). In the subjective test, in the anisometropic state in which +2D is added to the left eye, the first subject answered that the test target 503R of the right fixation target 500R is easy to see regardless of the test distance. Therefore, in the first subject, in the anisometropic state in which +2D is added to the left eye, the fixating eye is determined to be the right eye regardless of the test distance, and it is determined that there is no fixation alternation.

[0127] As a result, it is found that the first subject does not change the fixation eye between far vision and near vision, and adjusts to the test distance to see the target. Therefore, the examiner can evaluate the first subject as a type with low adaptability to monovision.

[0128] 7A to 7C show the results of the second subject. In the second subject, when both the left and right eyes E are in a perfect correction state, as shown in FIG. 7A, when the test distance is 0D to 3D, the difference between the refraction value of the left eye and the refraction value of the test eye and the refraction value corresponding to the presentation position of the fixation target is below a preset threshold (e.g., 0.5D) regardless of the test distance. When the test distance is 4D, the difference between the refraction value of the left eye and the refraction value of the right eye and the refraction value corresponding to the presentation position of the fixation target is about 1.2D (above the threshold). Therefore, it can be inferred that when both the left and right eyes of the second subject are in a perfect correction state and the test distance is 4D, the adjustment amount is insufficient and the focus is not adjusted.

[0129] In contrast, in the second subject, in the anisometropic state in which +2D was added to the right eye, as shown in Fig. 7B, when the test distance was 0D to 3D, the difference between the refraction value according to the fixation target presentation position and the refraction value of the left eye was almost 0D (below the threshold), and the difference between the refraction value according to the fixation target presentation position and the refraction value of the right eye was about 1.5D to 2D (above the threshold). On the other hand, when the test distance was 4D, the difference between the refraction value according to the fixation target presentation position and the refraction value of the left eye was about 0.8D (above the threshold), and the difference between the refraction value according to the fixation target presentation position and the refraction value of the right eye was about 1.2D (above the threshold). Therefore, in the second subject, in the anisometropic state in which +2D is added to the right eye, when the test distance is changed from 3D to 4D, the difference between the refraction value according to the presentation position of the fixation target and the refraction value of the left eye becomes large (0.2D to 1.2D), and the difference between the refraction value according to the presentation position of the fixation target and the refraction value of the right eye becomes small (1.5D to 0.8D). In other words, when the test distance is changed from 3D to 4D, the refraction value of the right eye approaches the refraction value according to the presentation position of the fixation target. Therefore, in the anisometropic state in which +2D is added to the right eye, the left eye is determined to be the fixating eye when the test distance is 0D to 3D, and the right eye is determined to be the fixating eye when the test distance is 4D. In the subjective test, in the anisometropic state with +2D added to the right eye, the second subject answered that the test target 503R of the right fixation target 500R looks slightly darker (easier to see) than the test target 503L when the test distance is 4D. Therefore, from the results of both the refraction measurement and the subjective test, it is determined that the second subject experienced a fixation alternation at the test distance of 4D in the anisometropic state with +2D added to the right eye. From these results of fixation alternation, the examiner can confirm that the refraction measurement results and the subjective test results are consistent.

[0130] In the second subject, in the anisometropic state in which +2D was added to the left eye, as shown in Fig. 7C, when the test distance was 0D to 3D, the difference between the refraction value according to the fixation target presentation position and the refraction value of the right eye was almost 0D (below the threshold), and the difference between the refraction value according to the fixation target presentation position and the refraction value of the left eye was about 2D (above the threshold). On the other hand, when the test distance was 4D, the difference between the refraction value according to the fixation target presentation position and the refraction value of the right eye was about 1.2D (above the threshold), and the difference between the refraction value according to the fixation target presentation position and the refraction value of the left eye was about 0.8D (above the threshold). Therefore, in the second subject, in the anisometropic state in which +2D is added to the left eye, when the test distance is changed from 3D to 4D, the difference between the refraction value according to the presentation position of the fixation target and the refraction value of the right eye becomes large (zero D to 1.2 D), and the difference between the refraction value according to the presentation position of the fixation target and the refraction value of the right eye becomes small (2D to 0.8D). In other words, when the test distance is changed from 3D to 4D, the refraction value of the left eye approaches the refraction value according to the presentation position of the fixation target. Therefore, in the second subject, in the anisometropic state in which +2D is added to the left eye, when the test distance is zero D to 3D, the right eye is determined to be the fixating eye, and when the test distance is 4D, the left eye is determined to be the fixating eye. In the subjective test, in the anisometropic state with +2D added to the left eye, the second subject answered that the test target 503L of the left fixation target 500L looks slightly darker (easier to see) than the test target 503R when the test distance is 4D. Therefore, from the results of both the refraction measurement and the subjective test, it is determined that the second subject experienced a fixation alternation at the test distance of 4D in the anisometropic state with +2D added to the left eye. From these results of fixation alternation, the examiner can confirm that the refraction measurement results and the subjective test results are consistent.

[0131] As a result, it can be seen that the second subject changes the fixation eye between distance and near vision, and tries to see the object with the eye with +2D added when near vision. Therefore, the examiner can evaluate the second subject as a type that is highly adaptable to monovision regardless of whether the left or right subject eye E is set for distance or near vision.

[0132] 8A to 8C show the results of the third subject. In the third subject, when both the left and right eyes E are in a perfect correction state, as shown in FIG. 8A, the difference between the refraction value of the left eye and the refraction value of the eye and the refraction value corresponding to the presentation position of the fixation target is equal to or less than a preset threshold value (e.g., 0.5D) regardless of the test distance, regardless of the test distance. Therefore, in the third subject, if both the left and right eyes are in a perfect correction state, it is determined that the left and right eyes E are able to fixate, regardless of the test distance.

[0133] In contrast, in the third subject, in the anisometropic state in which +2D was added to the right eye, as shown in Fig. 8B, when the test distance was 0D and 1D, the difference between the refraction value according to the fixation target presentation position and the refraction value of the left eye was almost 0D (below the threshold), and the difference between the refraction value according to the fixation target presentation position and the refraction value of the right eye was about 1.5D to 1.8D (above the threshold). On the other hand, when the test distance was 2D to 4D, the difference between the refraction value according to the fixation target presentation position and the refraction value of the left eye was about 1.2D to 1.5D (above the threshold), and the difference between the refraction value according to the fixation target presentation position and the refraction value of the right eye was about 0D to 0.2D (below the threshold). Therefore, in the anisometropic state of the third subject with +2D added to the right eye, the left eye is determined to be the fixating eye when the test distance is zero D and 1D, and the right eye is determined to be the fixating eye when the test distance is 2D to 4D. In the subjective test, in the anisometropic state with +2D added to the right eye, the third subject answered that the test target 503R of the right fixation target 500R looks darker (is easier to see) than the test target 503L when the test distance is 2D or more. Therefore, in the anisometropic state of the second subject with +2D added to the right eye, it is determined that fixation alternation has occurred at the test distance of 2D.

[0134] In addition, in the third subject, in the anisometropic state in which +2D is added to the left eye, the difference between the refraction value according to the presentation position of the fixation target and the refraction value of the right eye is approximately 0.5D or less (below the threshold) regardless of the test distance, as shown in FIG. 8C, and the difference between the refraction value according to the presentation position of the fixation target and the refraction value of the left eye is approximately 1.2D to 2D (above the threshold). In the subjective test, in the anisometropic state in which +2D is added to the left eye, the third subject answered that the test target 503R of the right fixation target 500R looks darker (is easier to see) than the test target 503L regardless of the test distance. Therefore, in the third subject, in the anisometropic state in which +2D is added to the left eye, the fixating eye is determined to be the right eye regardless of the test distance, and it is determined that there is no fixation alternation.

[0135] As a result, it can be seen that the third subject has a tendency to view objects with the right eye, which is the dominant eye. Therefore, the examiner can evaluate the third subject as a type that is highly suitable for monovision, in which the left eye is set for distance vision and the right eye for near vision.

[0136] The ophthalmic apparatus and the method for examining a subject's eye according to the present invention have been described above based on Example 1. However, the specific configuration is not limited to Example 1, and design changes and additions are permitted as long as they do not deviate from the gist of the invention according to each claim.

[0137] The ophthalmic device 100 of the first embodiment has a target presentation function, a phoropter function, and an autorefraction-keratometry function. However, the configuration of the ophthalmic device 100 is not limited to that of the first embodiment. For example, the ophthalmic device 100 may be configured with an external target device installed outside the device, and a device having a phoropter function and an autorefraction-keratometry function in combination. In this case, the presentation position of the target, i.e., the test distance, may be changed manually by the examiner or may be changed by communication control by the control unit 140.

[0138] In the ophthalmic apparatus 100 of the first embodiment, the examination distance and the spherical power (corrective power) of the left and right eyes E to be examined are changed by moving the focusing lens 45 of the optotype projection system 4 in the optical axis direction. However, the configuration for changing the examination distance and the spherical power is not limited to this. For example, the ophthalmic apparatus 100 may change the examination distance and the spherical power by moving the display 41 that displays the optotype in the optical axis direction. In addition, the spherical power of the eye E to be examined may be changed by appropriately inserting and removing a plurality of corrective lenses that are removably arranged on the optical axis of the optotype projection system 4.

[0139] In addition, the ophthalmologic apparatus 100 of the first embodiment has a left fixation target 500L presented to the left eye to be examined and a right fixation target 500R presented to the right eye to be examined as fixation targets, and an example has been shown in which the left fixation target 500L and the right fixation target 500R include fusion targets 502L and 502R that can be fused and test targets 503L and 503R that cannot be fused. However, the fixation target only needs to include at least a fusion target. Therefore, the left fixation target 500L and the right fixation target 500R do not need to include the test targets 503L and 503R.

[0140] Furthermore, the fixation target including the fusion target and the test target may be one for each of the left and right eyes E. In this case, for example, the subject can use polarized glasses or a compound eye 3D display to allow the left and right eyes E to view the test target individually.

[0141] In the ophthalmic apparatus 100 of the first embodiment, the position of the focusing lens 45 is changed until the perfect correction state of the left and right subject eyes E can be confirmed by using the RG test. However, in order to prescribe perfect correction values ​​for the left and right subject eyes E, for example, correction values ​​measured by a procedure other than the test method shown in Fig. 4 may be used, current eyeglass prescription values ​​already prescribed for the subject eyes E may be used, or perfect correction values ​​may be determined by performing multiple subjective tests.

[0142] In the examination method of the first embodiment, the refraction values ​​of the left and right test eyes E are measured for each examination distance even when the left and right test eyes E are in a perfect correction state. However, the refraction values ​​in the perfect correction state do not necessarily need to be measured.

[0143] In step S10 of the first embodiment, the main controller 141 continuously changes the presentation position of the fixation target while presenting it. However, this is not limited to this. The main controller 141 may change the presentation position of the fixation target stepwise by a preset distance (e.g., +1D). In this case, the examiner asks the subject how the test targets 503L and 503R look each time the presentation position of the fixation target is changed. In addition, when the main controller 141 changes the position of the fixation target stepwise, the main controller 141 may block the target during the movement so that it is not visible to the subject, and display the fixation target again after the presentation position of the fixation target is changed.

[0144] In addition, with respect to the above description of the first embodiment, the following will be further disclosed. (1) a target presentation unit that presents a fixation target to the left and right eyes to be examined; an objective measurement optical system for objectively measuring ocular characteristics of the left and right eyes to be examined, A control unit that controls the objective measurement optical system, the fixation target includes a fusion target that can be fused when viewed binocularly with the left and right test eyes, the target presenting unit presents the fixation target while changing a test distance from the left or right eye to the fixation target within a predetermined distance range when a prescription is given in which one of the left or right eye to be examined is maintained in a perfectly corrected state and the other of the left or right eye to be examined is corrected from the perfectly corrected state by a predetermined degree, The control unit measures the eye characteristics when the fixation target is viewed with both eyes by the objective measurement optical system, and obtains refractive values ​​of the left and right eyes to be examined as objective measurement information. An ophthalmic apparatus comprising: (2) In the ophthalmic device described in (1), The control unit intermittently acquires the objective measurement information at a timing when the test distance reaches a predetermined distance. An ophthalmic apparatus comprising: (3) In the ophthalmic apparatus described in (1), The control unit continuously acquires the objective measurement information while the test distance is being changed within the distance range. An ophthalmic apparatus comprising: (4) In the ophthalmic device according to any one of (1) to (3), the target presentation unit is controlled by the control unit and includes a left-eye light projection optical system that presents a left fixation target to the left eye to be examined, and a right-eye light projection optical system that presents a right fixation target to the right eye to be examined, The control unit performs a prescription for achieving the anisometropia using the left eye projection optical system and the right eye projection optical system. An ophthalmic apparatus comprising: (5) The ophthalmic device according to (4), The left fixation target and the right fixation target each include a fusion target that can be fused when the left eye to be examined visually recognizes the left fixation target and the right eye to be examined visually recognizes the right fixation target, and a test target that cannot be fused when the left eye to be examined visually recognizes the left fixation target and the right eye to be examined visually recognizes the right fixation target. An ophthalmic apparatus comprising: (6) In the ophthalmic device according to any one of (1) to (5), The control unit includes a fixation eye determination unit for determining a fixation eye based on the objective measurement information. An ophthalmic apparatus comprising: (7) The ophthalmic device according to (6), The fixation eye determination unit determines the subject's eye as the fixation eye, the difference between the refraction value according to the presentation position of the fixation target and the refraction value of the subject's eye itself being equal to or less than a preset threshold value, or determines the subject's eye as the fixation eye, the one of the left and right subjects' eyes which has a large decrease in the difference between the refraction value according to the presentation position of the fixation target and the refraction value of the subject's eye itself when the test distance is changed from far vision to near vision. An ophthalmic apparatus comprising: (8) a target presentation unit that presents fixation targets to the left and right eyes to be examined; an objective measurement optical system for objectively measuring ocular characteristics of the left and right eyes to be examined, A method for examining an eye to be examined using an ophthalmologic apparatus including a control unit for controlling the objective measurement optical system, a first step of controlling the objective measurement optical system so that, in a state where one of the left and right test eyes is maintained in a perfectly corrected state and the other of the left and right test eyes is corrected from the perfectly corrected state by a predetermined degree to obtain anisometropia, the target presenting unit presents the fixation target and changes a test distance from the left and right test eyes to the fixation target within a predetermined distance range, and the control unit measures the ocular characteristics when the fixation target is viewed with both eyes, and obtains refractive values ​​of the left and right test eyes as objective measurement information; a second step of controlling the objective measurement optical system so that, after the objective measurement information is obtained in the first step, the other of the left and right test eyes is maintained in the perfectly corrected state, and one of the left and right test eyes is corrected from the perfectly corrected state by a predetermined degree to obtain anisometropia, and the target presenting unit presents the fixation target and changes the test distance within the predetermined distance range, and the control unit measures the ocular characteristics when the fixation target is viewed with both eyes, and obtains refractive values ​​of the left and right test eyes as the objective measurement information; A method for examining an eye to be examined, comprising: (9) The method for examining an eye to be examined according to (8) above, and a third step of controlling the objective measurement optical system so that, before obtaining the objective measurement information in the first step, a prescription is made for both the left and right eyes to be examined so that the right and left eyes to be examined are in the perfectly corrected state, the target presenting unit presents the fixation target and changes the test distance within the predetermined distance range, and the control unit measures the ocular characteristics when the fixation target is viewed with both eyes, and obtains refractive values ​​of the right and left eyes to be examined as the objective measurement information. 13. A method for examining an eye to be examined, comprising: [Explanation of symbols]

[0145] 100 Ophthalmology equipment 125L Left measurement optical system 125R Right measurement optical system 122a Drive unit 140 Control section 141 Main control unit 4 Visual target projection system (target presentation unit) 6 Reflector measurement projection system (objective measurement optical system) 7 Reflector measurement receiving system (objective measurement optical system) 500L left fixation target 500R Right fixation target 502L Fusion optotype 502R Fusion optotype 503L Test Mark 503R Test Optic Mark

Claims

1. a target presenting unit that presents fixation targets to the left and right eyes to be examined; an objective measurement optical system for objectively measuring ocular characteristics of the left and right eyes to be examined, A control unit that controls the objective measurement optical system, the fixation target includes a fusion target that can be fused when viewed binocularly with the left and right test eyes, the target presenting unit presents the fixation target while changing a test distance from the left or right eye to the fixation target within a predetermined distance range when a prescription is given in which one of the left or right eye to be examined is maintained in a perfectly corrected state and the other of the left or right eye to be examined is corrected from the perfectly corrected state by a predetermined degree, The control unit measures the eye characteristics when the fixation target is viewed with both eyes by the objective measurement optical system, and obtains refractive values ​​of the left and right eyes to be examined as objective measurement information. An ophthalmic apparatus comprising:

2. 2. The ophthalmic apparatus according to claim 1, The control unit intermittently acquires the objective measurement information at a timing when the test distance reaches a predetermined distance. An ophthalmic apparatus comprising:

3. 2. The ophthalmic apparatus according to claim 1, The control unit continuously acquires the objective measurement information while the test distance is being changed within the distance range. An ophthalmic apparatus comprising:

4. The ophthalmic apparatus according to any one of claims 1 to 3, the target presentation unit is controlled by the control unit and includes a left-eye light projection optical system that presents a left fixation target to the left eye to be examined, and a right-eye light projection optical system that presents a right fixation target to the right eye to be examined, The control unit performs a prescription for achieving the anisometropia using the left eye projection optical system and the right eye projection optical system. An ophthalmic apparatus comprising:

5. 5. The ophthalmic apparatus according to claim 4, The left fixation target and the right fixation target each include a fusion target that can be fused when the left eye to be examined visually recognizes the left fixation target and the right eye to be examined visually recognizes the right fixation target, and a test target that cannot be fused when the left eye to be examined visually recognizes the left fixation target and the right eye to be examined visually recognizes the right fixation target. An ophthalmic apparatus comprising:

6. The ophthalmic apparatus according to any one of claims 1 to 3, The control unit includes a fixation eye determination unit for determining a fixation eye based on the objective measurement information. An ophthalmic apparatus comprising:

7. 7. The ophthalmic apparatus according to claim 6, The fixation eye determination unit determines the subject's eye as the fixation eye, the difference between the refraction value according to the presentation position of the fixation target and the refraction value of the subject's eye itself being equal to or less than a preset threshold value, or determines the subject's eye as the fixation eye, the one of the left and right subjects' eyes which has a large decrease in the difference between the refraction value according to the presentation position of the fixation target and the refraction value of the subject's eye itself when the test distance is changed from far vision to near vision. An ophthalmic apparatus comprising:

8. a target presenting unit that presents fixation targets to the left and right eyes to be examined; an objective measurement optical system for objectively measuring ocular characteristics of the left and right eyes to be examined, A method for examining an eye to be examined using an ophthalmologic apparatus including a control unit for controlling the objective measurement optical system, a first step of controlling the objective measurement optical system so that, in a state in which one of the left and right test eyes is maintained in a perfectly corrected state and the other of the left and right test eyes is corrected from the perfectly corrected state by a predetermined degree to obtain anisometropia, the target presenting unit presents the fixation target and changes a test distance from the left and right test eyes to the fixation target within a predetermined distance range, and the control unit measures the ocular characteristics when the fixation target is viewed with both eyes, and obtains refractive values ​​of the left and right test eyes as objective measurement information; a second step of controlling the objective measurement optical system so that, after the objective measurement information is obtained in the first step, the other of the left and right test eyes is maintained in the perfectly corrected state, and one of the left and right test eyes is corrected from the perfectly corrected state by a predetermined degree to obtain anisometropia, and the target presenting unit presents the fixation target and changes the test distance within the predetermined distance range, and the control unit measures the ocular characteristics when the fixation target is viewed with both eyes, and obtains refractive values ​​of the left and right test eyes as the objective measurement information; A method for examining an eye to be examined, comprising:

9. 9. The method for examining an eye to be examined according to claim 8, and a third step of controlling the objective measurement optical system so that, before obtaining the objective measurement information in the first step, a prescription is made for both the left and right eyes to be examined so that the right and left eyes to be examined are in the perfectly corrected state, the target presenting unit presents the fixation target and changes the test distance within the predetermined distance range, and the control unit measures the ocular characteristics when the fixation target is viewed with both eyes, and obtains refractive values ​​of the right and left eyes to be examined as the objective measurement information.

13. A method for examining an eye to be examined, comprising:

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